SFOE standard catalogue · Heating Technology · Version 2.0
Replacement of Electric Water Heaters in Buildings
The goal is to estimate the electricity savings triggered by replacing conventional electric water heaters in buildings with water heating powered by renewable energy sources (centralized or decentralized).
Examples and Scenarios
What the measure delivers
5.0 Rp./kWh
Scenario A
Replacement of 10 decentralized electric boilers in a residential building with 6 primary residences and 4 secondary residences
83'200kWh
eligible kWh, accumulated over the measure's lifetime
Funding contributionCHF 4’160
Inputs: 6 Erstwohnungen MFH, 4 Zweitwohnungen MFH
Scenario B
Replacement of a central electric boiler in a café with 20 seats
46'000kWh
eligible kWh, accumulated over the measure's lifetime
Funding contributionCHF 2’300
Inputs: 20 Sitzplätze Restaurant / Café
Requirements
Only measures that meet the requirements of the Energy Ordinance (SR 730.01; EnV) can be credited. The additional requirements for the technical characteristics and for the implementation of the measure are set out in Table 1.
Old system
New system
Technology
Conventional electric built-in water heater within the scope of Annex 1.15 EnEV
-
Energy source
100% electricity
≥ 60% wood, solar, ambient or district heat.
The use of electric heating elements as supplementary heating is not permitted.
Energy efficiency
-
Water heaters with a heat pump must be certified with a valid FWS quality label.
Solar collectors of solar-powered water heaters must be certified with a valid Solar Keymark quality label.
Implementation
The replacement and commissioning of the new system must be carried out by a qualified specialist or company.
Disposal
The consumption-relevant components of the old devices may not continue to be operated within Switzerland. Proper disposal or export must be demonstrable on request.
Proof of compliance
Compliance with the requirements must be demonstrated by the following documents. The documents listed in Table 2 are an integral part of the proof of measure implementation.
1.Explanation (PDF format, max. 2 A4 pages) of how it is ensured that the replaced devices were properly disposed of (e.g. by means of declarations, disposal items on contractor invoices, etc.).
2.Invoice documents (PDF, PNG or JPEG format)
Calculation basics: symbols, units and formulasNot needed for the review, useful for recalculating▾
Symbols, Terms and Units
Symbol
Description
Unit
E
annual electricity consumption
kWh/a
ΔEeco
cumulative electricity savings
kWh
f
Factor
—
Ns
Standard effective duration
a
V
Hot water volume
l/d
η
Utilization rate
—
Calculation Formulas
Cumulative Electricity Savings
ΔEeco = (Eold - Enew) × feco × Ns
The cumulative electricity savings result from the difference between the electricity consumption of the old and new state, multiplied by the reduction factor and the standard effective duration.
Annual Electricity Consumption
Ex = (1/η_x) × ρ·cp × Δθ_gen × Σ(fP,i × di × 1.5 × ni × VW,u,i)
The annual electricity consumption depends on the daily hot water demand and the heat losses of the storage and pipes.
Downloads
Documentation (PDF)Complete technical documentation including calculation basisDownload DOC
Excel Calculator (XLSX)Interactive calculation tool for savingsDownload PRO
Standardised measures are one of two measure types in the EFFEL programme (efficiency improvements by electricity suppliers, Art. 46b EnG). They follow a predefined SFOE catalogue with fixed savings values.